<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <script src="jquery-1.11.3.min.js"></script>
    <title>Document</title>
    <style>
        /**蒙层*/
        .left_slide_center_nav .center_mask {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(0, 0, 0, .6);
            z-index: 1000;
            display: none;
        }

        /**内容*/
        .left_slide_center_nav .center_content {
            position: fixed;
            width: 80%;
            top: 0;
            bottom: 0;
            left: 0;
            transition: all .5s;
            -moz-transition: all .5s;
            -webkit-transition: all .5s;
            -o-transition: all .5s;
            -os-transition: all .5s;
            z-index: 99999;
            box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
            overflow-y: scroll;
            background: #fff;
            -os-transform: translateX(129%);
            transform: translateX(129%);
        }

        /**显示蒙层和内容 使用父级.show样式控制*/
        .left_slide_center_nav.show .center_mask {
            display: block;
        }

        .left_slide_center_nav.show .center_content {
            -os-transform: translateX(0);
            transform: translateX(0);
        }
        .close{
            float:left;
            width:20px;
            height: 20px;
            margin-right: 10px;
            margin-top: 10px;
        }
    </style>
</head>

<body>
    <div class="slide">
          点击划入
    </div>
    <div class="left_slide_center_nav">
        <!--蒙层-->
        <div class="center_mask"></div>
        <div class="center_content">
            <!-- 内容 -->
            <div class="close">
                 X
            </div>
        </div>
    </div>
    <script>
        $(".slide").click(function(){
            $(".left_slide_center_nav").addClass("show");
        })
        $(".close").click(function(){
            $(".left_slide_center_nav").removeClass("show");
        })
        //点击蒙层关闭：
        $(".left_slide_center_nav").on("click", ".center_mask", function () {
            //隐藏：
            $(".left_slide_center_nav").removeClass("show");
        });
    </script>
</body>

</html>